Engine control device



Alli l5, 1944- c. H. JORGENsEN Erm. 2,356,063

y ENGINE CONTROL DEVICE Y AFiled Sept. 23, 1937 3 Sheets-Sheet 3 :im i L 324 3 32a 3/,5' :f L-A// l r /30a 2'32 E u i A96 3/4 a 33 23 226 zzz :34 36 525 yZ?! F 7 INVENTORS /arenae HJmlqenss/v v Lawrence Eerm/qga ATTORNEYS Patented Aug. 15, 1944 um@ STATE ENGINE coN'rrtoLpEvIo'E f Clarence H.` Anderson,

Corporatiom Delaware Jorgensen and Lawrence C.Dermond,

Incl.,l assignors tojGeneral Motors Detroit, Mich., a'corporation of Application september 23, ioaauseriai `No.1c5326 e i es claims. (cinc-1.79)," c I e.

the provision oi'fagsingle control vunit'provided ,o

This invention relates to an improved construction inrwhich mechanism for automatically controlling the position of the choke in accordance with temperature and various engine operating conditions and a starter control-switch which is automatically regulated in accordance with various engine operating conditions are em- 'bodied in thesame control unit.

`It has been previously the custom to provide an automatic choke controlling mechanism in which means are'provided that `are effective to determine the position Vof the choke in'accordance with the joint action of engine temperature, engine suction and under some circum-fstances', the action ofthe throttle. It is also old and well known to provide a `semi-automatic starter` control system Vin which a control switch isr operatedby the Vaccelerator pedal to close'the starter circuit as the accelerator pedal is moved to open the throttle and is operated to open the starter circuit when, the engine starts to run under its own power, said Aswitch being opened generally by action, of engine suction, the'generator, or the joint action of both suction and 26 the generator. Y y

According to the present invention these two engine controlling instrumentalities have been combined in one unit and. lt is the principal purpose of the invention yto simplify and improve the construction of the automatic choke and control switch mechanism, so as to lmake the device.

'more cheaply, render itmore positive and accurate in action, 'eliminateyduplication of and superfluousI partsfprovide,'af/control lfor thev starter system which is effective under any possible condition to give the desired results, andto generally improve the function of the device, both withv respect to the control of the choke and op.- eration of the starter control switch.

, rWith these objects in view, one featureof the invention consists in the provision of iniproved means for controlling the chokev valve under ac-` celerating conditions which mechanism s effective lto more positively and accurately control the position of thev choke valve to give the bestfresults and provide the proper mixture ratios for acceleration under all operating con;

ditions and at all speeds.`

`A further feature o f the invention resides in the provision of means operable by thev throttle valve, itself, for controlling the operation of the choke valve under certain conditions and for controlling the operation of the engine starting motor. Y

'A4 further feature ofthe invention resides in 55 suction'fandfo'r 'disablingthe startingV ,system lwhen the 'engine is operating `under itsown power. V j 'fr A further feature' yof the invention resides in the provision oi' a throttle-operated cam of speciflc design eiective to" control the positionof -the choke valve"duringfacceleration to Vprovide the desired 'mixture' ratios and r`alsov-` effective to `operate 'the *controll switch of lthe starting systemto causev the starter 'to become etlectivfelonly when the throttle is in the desired position for startingi f ;-V Y f, n A still additional fe'aturei of Vthe A invention ref` sidesin the provision of improvedlatching means forregulating the action of the control switch to prevent any Ypossible opening ofthe control switch during engine cranking and also is 4ef fective toprevent any v'possibleclosingof the control switch during `engine operation."`

Another feature of the'in'vention consistsin thel c provision. of` improved'rneans for' controlling' the-` speed of movement ofthe choke valve toward scription', reference being had totheaccompany-Y,- ing drawings whereina preferred embodiment of the present `invention is clearly shown. In thedrawings:

Fig. 1 is a side elevation of a dual carburetor u inwhich the automatic:mechanisml for control,- `ling the. actionof the chokefvalve and the en# ginestarter is embodied.

`Fig.,2 is a section along the line A2-1-27of 1r with'certain parts shown in elevation. A

,1P-ig. 3 is ahorizontal section on the line v3 3 of Fig. 2 with certain parts lshown inrelevation.l

4in of Fig. 3.;

Fig. 4 is a detailed sectional viewon the line- Fig. 5 is adiagrammaticfsection partly in elef vation of the whole unit. l

Fig. 6 is a demnedsecuonal view of the switchf' operating mechanism showing the parts in theV position occupied while the engine is being` Figj'l isV a diagrammatic view. ofthe circuit v of the starter controlledsystem.

Referring primarily to Figs.`1"and 5, the refer-v ence numeral IU indicates the carburetorr in its entirety, such carburetor being provided with two intake passages ,Ily andI n surrounds thev instill, Wilnis y 0111v a shaft!!! .vfliifhfwifiv the F5115 ofthe yairii'llet 3,4

, ner. To enablethisa sleeves, .cated :in 1mg.. .1.

lower end of the ,shaft ilioo .v v

`stat is riveted, as indicated Ain ria-,2. A

portion of the bracket il U-lhaped in form, the

l U-shaped'smelnber is' o ormay be `a chamber'connected for use corn'-l l bining WhatishwWnn'the 9.112,38 a. vhot spotf,

This chamber r,supplies the lheat vthatis utilized .to heat thethermostatv which regulateathe choke valve -in a. manner ,hereinafterv more scribed.

An operating connection for the throttle-shaft of a conventionality-peg tnrotnesnaft to an accelerator pump, this, mech;

anism being no part; ofy thepresent,y invention.

An.v unbalanced' V valve l2fis -positionedin the. air inletwll; andthe. valvezgin `eeured om center vjonrnaled for i rotation in and isvoperablelby the pressure. of the incoming yair. n' .-'Lhisvalve.L obgviously regulatesthegadrnission of airlto thelcarburetorand the air nowingpastsuch valve is mixed -withfuel toform the mixture which isy suppliedV by the.' passages t2- andI IQ Vto:` theaengine.

,mentales previously.indietedish-mechsnisn f l .beinsgpositionedfwithin ahcusins-uwhich is securedV to the-main housing-of the carburetorlby machine screl'sy L or: inl. any; other suitable mans @haal-'1m' 'tofatutethe' valvesil, the` shaft t Il M fconnectedin ,y any lsuitable manner .to oneend ofa exiblecable 42' which; as shown in the drawings;v projects intofa the uppery end: Qfshafttewhichisiqumaled in receivsdiathe housing n Vindi- The shaft!! lis suitably Jourl,naledfor-rotation and alsoiournaled-for rotation on thesleeve in 4 y n e stitute a. part o1'y thisinvention landis not shown herein. iS a semental gearxryz, by means of which the suction operated mechani'sxn'is adapted to rotate the shaftv 4l, suchL suction operating mechanism operating through the medium of rthethermostat as willbenow'described.:

Dependinglfrom the segmental gearisa pine!!- which is suitablysecured `to4 the segmental 'gear' and engages in 1a slotl 5,6 -iorniedggin ja kbiijurcated-vv member 58, best shown. inliig; 5,- which issecured by rivets, or in any, other desirableway, @toa therdmostat Ill which ispreferablylin the-form of a spiral coil-that .surrounds theI lowery endfof the. shaft `@land has its lowerfend secured to the bottom of theshaft, the thermostat extending' longitudinally of the shaftv fromfthegear seg,- ment to thelowerend of said shaft. Y

The means for securing the thermostat tothe 4l is capable of adjust.-

ment in order to -vary thefOrce exerted by the f Vthermostat on .the

Shaft 4 8. lfor ,any v gwen temperature when the temperature is low.

`This meansincludes a member yor vbracket is provided which; ishnot shown Aand a connection `30 extends fromthea;

" vto the shaft.

fullydei member 66 in l-which .engage-'teeth `1I 'surface o1'= thepiston member 1'8 received within Y vthepiston 2.0.A

t gine is not.. running, vis "heid f in lower arm ofthe .Ulndicated by reference numoral Il having an oriiice therein through which ythe-lowery endjcf the shaft dljpasses, while the upper arm` I Ixoi' they U -chaped member is bifurcated andreceivesthe shaft between the two forks thereo'tf` The verticalzportion Il of the provided with an orifice in is threaded so that thenend the reduced portion 12 of which a set screw A'HI of the screw engages the shaft .Il and may v'I'hevgearseg'nient v524 is provided with teeth 'lly formed on the exteriorv vtt-,cylinder l0 foimedlwithin thehousing 3l and' isjnormally adapted to be held in the positionxshownv in Fig. 5 by a spring l2, which is received in the cylinder between the end thereofand the. piston .which is partially hollow to embrace the spring. -The piston slides within the cylinder due v tot the suction of the engine and underftheiniiuencerof other forces as will be moreparticularly,` set 'forth hereinafter, but when itis held in anyllgivenposition by the springs-l2', or byany otherfmeans, a change will cause expansion or contraction ofthe thermostat and iffth'e piston be stationary at this time, 'thegeanr segment |52 is held stationary so that, this expansion or contraction of thethermostat willcause the free end'thereof to move and `touso rotatelthe shaft 48. which, Ithrough the `.iieiribl'e connection 4,2 Ipreviously ,describedg' will ymove `the valve towardv open or closed' position,v

expansion ofthe thermostat due: to a` rise in temperature causing the valveto open and contrac- A,tion of `the thermostat'having the reverseeiiect 4and causing the valve to close.

v'The vsuction-operated piston .hereinafter re- L1ex1'edtor under normal `conditions when theenofzthe cylinder'in which it slides by the spring soon as `the engine starts to rotate when it isbeing turned .by the startingl motor during thefcranking period andbefore the` engine starts to cated to the cylinder in through the passage Il which connects with a sump-or chamber 08; indicated infdotted lines in Fig. 2, formed within the housing and this in turn connects 'with a passage ,t8 also indicated in vthrottle valves 'I6 and dot-ted lines in Fig. which communicates with the carburetorintake passage Just posterior to the of .passages the manifold vacuum is communicated to the cylinder to the-'right ofthe piston ment ofthe piston to the ien.

The piston 'I8 is provided with a hollowy extensionl finto which. projects a rod 9 2 which extends-through a closure-member secured in po- 02 to which the lower end .of the -thCImQ-"N sition at-the'end 0f theextension 90 in anysuitable mannen The rod 92 has an enlarged head be tightened to secureI the any desired position with respectl in n temperature position at they leftvrun-under its own power, suction is communi- `which the pistonlslides.

It. Through this series rises. The heater tube maybe a single tube. or

it maybesurroundedwith anotlter tube |83 which i'itsoutside oi'this .heater tube and ii-used would serve a` double purpose; nrst, .togivethe heater tube some more,-

emciency and second, to protect the heater ,tu'be covering, dirt, Water, etc. fromentering the housing and from contact with the thermostat.

AThe preceding portion of .this speciiication relates to the construction of the control unit vwhich operates the choke valve to regulate the mixture proportions. According'` to the presentinvention there is embodied in this sa-me control a switch which controls the .action ofthe engine starter andthe operation ofwhichiscontrolled by the position of the throttle valve.,-

switch mechansm'is vpositioned .withinja' housing indi- "cated in its entirety by the reference' numeral |10 and which isl adapted to be securedat the right handend of the' cylinder 80 as` shown best in Fig. 2. The housing is provided with projecting ears i12 and |14 which are secured bymachine screws |18 to the wall voi? the main unit'housing sa e gasket 11s being providedtojf'rfm might joint between the main housing .and the supplemental switch housing |10.- The switch comprises two contacts |80 and` |82, contact |80being supported by a spring arm |84 which is .bent'at right angles as indicated in Fig. and is securedto the housing n| by rivets |88 but insulated therefrom tact |82 is supported by a contant arm |90 of relatively rigid material which is.bent at right angles and that portion of such arm most distant from the contact is separatedfrom thehousing |10 by a. washer of insulating material |82 and is secured inthehousingbyv rivets |.94 or inf-any other desirable 'wayl Binding posts v|88 and |98 are provided, to which the wires leading from the' 'starter control circuit tfthe svntch formed' bythe contacts r|8|l and `|8 2 were conair and thus increase the.

yaasaoss y t such that when the throttle'lis infullycloscd position, asshown in Fig. 5'.the rod occupies a position far enough to the 'right-'to hold the contact |80 out of4 engagementwith the ''xed contact-|82 and-vin order for'these contacts `to closegthethrottle must move.. toward open posi- I Thelmeans which is'fcontrolledv by engine Vsuction; for operating or controllingtheswitch comprisingcontaots |80 and |82 consists primarily in a cam2| 2 .which is rotatably mounted on a Astud 2|4 securedin the wall of the *housing |10.

Projecting from the cam' is an arm 2|6 to which y ispivotally connectedalink 2|8, the other end of whichis pivotally connected-to an ear 220 formed on van angle-.shaped member 222 which is secured y byarivet224 to a diaphragm 228 the outer edge of which is'securedbetweena flange 228 projecting from a cup-'shaped metal shelll 230 and a cooperating 'flange 232.formed on the'housingillr.

. The edgeof the shell-230 is ycrimped or spun vet around the flange 232. as vindicated in Fig. 4 of the. drawingsto hold 4the diaphragm tightly between the flanges 228 and 232 and. form a leadproof .ioints- Washers;234 and 236 are provided on opposite sides of the diaphragm and are held by washers |88 of insulating material. AThe connected. Thisci'rcuit will bcv more fully` described hereinafter.

A spring 200 is received between the spring arm |84 and ascrew 202 threaded in the housing .|10. This spring tendsto' movethe spring4 arm |84 iin a direction tocl'ose the contacts |80and'v |82 and by removal of the screw`202,.springs of, diierent strength or length canfbe substituted to adjust at al1 times when theen'gine' is voperatin matter how low the -engine speed. v .v v

In order that the throttle in its movement may control the action of these .'nt ac i :s,I an arrn .204 j is secured to the throttle shaft by riveting such arm to the cam |30, or in any 'other suitable way'. This arm 204 carries a' projecting lip or lug'208 which is adapted to engage a rod 208 s lidable in a bore in the wall oi.' the main housing38and'having a reducedend 2|0 whichis Vdesigneciltocontact with the spring arm 'I 84` to whichthe movable"coritct |80 is secured; r The "construction Oflthe arm 2044 andthe length of 'therod 2v08`f"are in assembledposition by the rivet 224 previously referred to. The washer 236 engagesa spring V238 which is received between such` washer and a shoulder 240. formed on the inside of the housing |10, saidspring beingadapted to hold the diaphragm in the position shown in Figs. 2 and 5,- when there is,no.suction eiective on such diaphragm or whenthe suction which is 'effective thereon yis insucientto` overcome the pressure oithespring. g

,.Eiuction is communicated to the interiorof the :housing `lill-through the opening 242`which registers with the cylinder 80 when thehousing |10 is assembled iny positionon the housing 38, las

shown in Fig..3 ofthe drawings.

Itwill be apparent. from considerationof-Fig. 5 that the spring .arm |84, which carries contact |80, has projecting therefrom a pin-250 and when thel cam 2|2 Vis in such position that the high surface thereonengagesthe pin-1250, lthe contacts |80 and |82 can never engage. Theca'm'is moved to this position by the action of the engine-suction,. as will bemore fully explained later and when itis in such position, it isprevente'd from returning to the positionoccupied. in Fig. 5 so Along asA the pin 250 remains on the cam Asurface 2i2by reason-of a projecting toe or latching member 252 which extends beyond the periphery of the cam and isadapted to engage the pin'250. Asv will bepointed out later, the cam assumes vsuch position upon increased engine suction'that the high surfacethereof engages the'pin250, and

it ,cannot bev returned to the position shown in Eig` 5 in which position the contacts |80 and |82 are permitted vto close whenever the throttle is moved to such position as toallow suchclo'sing, until the throttle is moved to fullyc'losed position which releases the pin 250 fromthe latch 252 and allows-.thecam 2|2 to be moved by the i spring 238. to the position shown in Fig. 5 of the drawings. e. Y

vitis obvious from inspection of Fig. 5 thatI the A suction eifect on thediaphragm 226 will move the link 2|8 upwardly to rotate the cam in a'clockwise direction in order that .the highv surface may becbrought. opposite the pin 250. It is, however necessary that such place during the cranking of the engine because such movement of. the camwould separate the rotation shouldA not take 2,356,063 contacts isn and lszfona if it took place duringcrankng, the engine -might not be started. Means are, therefore, provided to prevent the movement of the cam in the manner described until the engine suction is higher than is ever possible when operating it at cranking speed. The means for accomplishing this result comprises a spring detent which includes the spring i pressed ball 254 whichengages an orifice or depression 256 in a sleeve 258 which is secured to the cam 2|2 and surrounds the stud 264. This sleeve is rotated with the cam and the spring held'l ball exerts sufficient pressure against its" seat to prevent anyrotary motion of the sleeve until kthe vacuum becomes higher than is ever produced when the engine is rotated by the starting motorl during cranking. In fact the spring whichholds the ball 254 inengagement with its seat in thesleeve 258 is of suiiicient strengthto prevent any rotary movement of the sleeve until a vacuum of ,3l/2 to 6 inches of mercury is reached. a The operation of thiscontrol switch during various engine operating conditions will be morecfully described hereinafter. In view of y, the; provision rof this detent arrangement avery light diaphragm spring can be employed and so lighty a, spring is used that a suction of 1/2" of mercury is enough to hold the switchopen against the pressure of such spring. This prevents any possiblevclosing of the switches aslong as the engine is running under any possible operating condition;

In Fig. '7 of the drawings there is provided a diagrammatic view showing the control switch,

Y the connections from the accelerator pedal to operate` the throttle and the circuit of a preferred form of control device for the starting motor with which the control switch previouslydescribed is adaptedto cooperate.

Referring to this figure, the starting motor is` indicated at 2604 and is provided with a shaft 262 on which slides a driving assembly through which the motion of the starting motor shaft is communicatedito the engine flywheel gear which is indicated at 264. This assembly includes a sleeve 266 which is splined to the motor shaft 262 but' slidable thereon, an overrunning clutch indicated in general by the reference numeral 268 and having .one member thereof secured tothe sleeve 266 and the otherv to a driving pinion 210 which is adapted to be moved into engagement with the engine Viiywheel gear 264. The whole assembly including the clutch, sleeve and pinion is adapted to be moved to the right to its gear meshing position by a, lever 212 pivotally supported at 214 and the lower end of which engages a collar 216 slidable on the sleeve 266 and adapted to be held in the position shown by a coil spring 218 which is received between the collar and the clutch. When the lever 212 is moved in a counterclocli Wise direction it tends to move 'the entire driving assembly to the right sufficiently for the pinion 210 to be -meshed with the gear 264 and if the teeth of the pinion and gear are so positioned that theV pinion` can slide into gear without abutment of the teeth, the assembly will be so moved. If, however, the pinion teeth abut those of the gear 264, the motion of the pinion to the right will be stopped but the lever will continue to move compressing the spring 218.

At the upper end the lever is connected to the armature 2810 of a magnet which must be en.-

ergized to move the lever 212 andfat the opposite end the armature is provided with an enlarged head 282 which engages the movable contact 284 of the "main starter switch which comprises ln addition fixed contacts 286 and i288 and is norf mally held open by the pressure oi a spring 290.-

When the motion of the lever 212 yasl described, is effective to move the movable contact 284 into engagement with contacts 288 and 288, the circuit of the starting` motor is closed and the shaft 262 thereof is rotated. This rotation of the shaft -will move ltheV pinion v210 sufficiently to relieve the condition of toothabutment above referred to and the spring 218 being collapsed and under pressure will immediately `force the pinion into engagement with the engine gear-264.

The driving mechanism with the exception ofthe pinion shifting means, above described is not" a portion `of this invention in its detailed construction and is substantially Whathas 'been in public use for many years. Whilek the magnet above referred to Visnot shown as of the same' detailed construction as what has beeninuse for some years on the Buick and other auto-'- mobiles, the identical magnet which has been so used can be used in place of that shown in the" drawings, thel only purpose .of thisdisclosure being illustrative, and' is f purely diagrammatic, the details of the magnet being entirely unim-I portant so far as this invention is concerned.

The starting motor Switch previously referred .to is in circuit with abattery indicated :at-,292, th'e fixed contact 266 being connected'by the `lead 294 to the battery vand is grounded through the connection 2796. The other contact 288 of the starting motor switch is connected by the wire 298 to the commutator of the startingmotor and is grounded throughk t-he connection -300. Ob. viously, when the contact 284 engages the contacts 288 and 288 current willpass from the battery 'through the lead 294, the switch ,comprising contacts abovereferred to, lead 29,8 to the starting motor and through the connection 300 to ground from which it will pass through con- ,v

nection 296 to the battery.

The closing of the above described effected las has previously been stated, by the action of a magnet having the armature 280. The

magnet is provided with a winding designated by` to the battery.- Obviously, when the contacts and |82 fare in engagement, current will flow from the battery through wire 294, wire.324, the ignition switch, wire 3|8 and wire 3|6 to the movable contact |80, thence through the iixed` Y contactV |82 when such switch is closed, to the. -bolt |94 and through thewiire 3|4-to the winding 3|0 and thence to` ground through the connec tion 3|2. The closing of the ignition switch at anytime that the control-switch comprising con-f tacts |80 and |82 are closed, will, therefore, cause energization of the magnet and the motion of the armature 280 to the left with the result that the pinion 2104 is placed in driving relation with the gear 264 and the main starting motor switch comprising contacts 284, l28|' and 288 is closed to complete the circuit ofthe starting motor and cause the latter to operate. If either the ignition switch or the switch comprising contacts |801 and |82 beppen, the circuit of the starting motor cannot be closed and the switch comprising, contacts` |80. and* |872, is always Amaintained in an open' conditio'ri' during operation of the engine under its own power so rthat the starting motor can never be rendered operative while theengine isrunning. A v

The generator charging circuit comprises the wire 294 -which leadsto the battery and the wire 3.26 is 'connected therewith and extends tov the generator-328 which is connected toV ground through the connection330. The' usual cut-out relay is indicatedvat 332.

Operation 4So far as the .operation ofthat portion ofthe unit whichcontrols the operation of the choke valve isconcerned, the operation is not greatly different from the choke operating mechanism.

used on the`193'7 Buick automobile,-as the constructionv of the'device herein disclosed `is not greatly different :from that one, the essentials of constructionY being the same and differing only in certain details.'

rIf it befassumed' that the engine is at rest and cold, with the throttle in closed position, the piston '|8` is Ain its left hand position, as shown Jin Fig. 5, having been moved to thatl position by the cooperative'action of the spring 82 and the thermostatv 60, which uponv contraction moves thel piston to the left untillitsmotionis stopped by engagement of. the eccentric member |44 with its cooperating stop. With parts in this position,

thechoke valve is held closed by a force which varies inversely as vthe temperature. However,

since thefythermostat is held at one end by the spring 82 through the rack and segmentalgear '16 and 14, the force exerted on such valve is no greater than :the strength of spring 82 in its extended, position. o

When the'starting motor circuit is closed and the starting Amotor is .rendered operative for the' purposeof rotating the engine in order to start it, said-engine rotation creates suction or -a partialvacuum in the intake lmanifold which is communicated to the cylinder 80 toV the vright of pistori 18. Due .to theslow rotation 1of the engine atv this time, howeverfthe suction created is insuflcient to 'overcomefthe forces holding the plstcn'tothe left and if the engine failed to start and the cranking period were prolonged, the engine would vbe -ooded unless `means were pro-. vided to prevent such jaction. f Such a means 'is provided and is operable by the throttle to open the choke valve during cranking if this be-found necessary.;

To accomplish this result, the throttle operates so as to move arm H2 out of the path of spring |04 to permitsuch spring to move to theright of the dash `pot piston 98, however, retards the l ing effect of the dash pot is, therefore, dimin- .ished as the piston is moved to the right byA reason contacts |80 and |82 cannot' engage until 'the throttle reaches such position.l There is, however, so much lost motion between the flange |02 and the extension 90 of piston 'I8 that the throttle can `be moved to the position necessaryfor the switch to close without the accompanying movement of the rod causing any opening ofthe choke valve. j

When v the engine starts to run under its own power, the suction effective on the piston ``l8 greatlyv increases, 'as well as,V the ow ofv alrj through the carburetor which is Veffective on theunbalanced choke valve and these forces are enough to overcome the pressure exerted'by spring 82 and the resistance of the dash pot to effect.

opening of the choke valve to a position determined by the suction `and air ow. The action movement of -the piston and thus prevents too rapid'opening movement of the choke valve, or movement of the valve too far toward open position, in this way preventing the admission of` sufficient airto lean the mixture to an undeslrable extent when the engine is operating under its own power during the warm up period.

If, after the engine is operating under its own power, the throttle be opened to accelerate the engine, the spring arm |04 and the dashv pot piston 98 cooperate to providea mixture of-proper proportions during this period, but .itis not desirable that the mixture be enriched enough to cause loading. Whenever the throttle is opened,

the suction is reduced and the spring 82 tends r to lforce the piston toward the left to eiect a closing movement of the choke valve. This closing' movement of the choke valve is controlled by the action of. the dash p ot and the spring arm m4.

every time the throttle isopened. The spring |04 is stronger than Yspring 82, but exerts no force to move piston 18 to the right when the parts are in the position shown in Fig. 2, because of the action of spring I6'.` When the throttlecpens,

however, the pressure of the yoke on the opposite endofspring |04 builds up the pressure of such' spring as arm ||2jis moved out of the path thereof, so that the pressure exerted'thereby on the With the structure disclosed, if it be assumedI that the engine is operating at relatively low speed with but `slightly open throttle, the piston 18 stands somewhat to the right and the flange |02 may be a considerable distance from the extension 90 of piston '18. When the throttle is opened the suction effective on' the piston'l immediately drops with the result that the spring 82 moves the piston toward the left to effect closingof the choke valve.

' |02 when it; will be stopped by the vpressure of piston is considerably greater than. thepressure of spring82,A This'action willmove therod 92,

theright as rapidly asl the' dash. p o.t .piston 98 spring arm 04.

piston will be moved back toward the right as the throttle continues toward open position so that the closing movement of the choke valve is only temporary. Thus the rst action occurring upon opening movement of the throttle is -a closing of 'f the choke valve, followed byv a secondfac't'ion"A which is an opening of' the valve duet-:tothe opening-movement of" the throttle which rotates"v camv |30, increasingI the forceofspringarmy |049 andmoving the piston `10 toward' the right against 'l 4' This movement willy be rapid until the extension 90 strikes the ange Also after the extension env gagesthe ange |02, the assembly including the the pressure of spring 82, to again move the choke opened for acceleration after it has reached a position Where the surface |30b of arm |30 is en gaged by its cooperating roller there will be substantially no temporary closing of the choke for acceleration purposes because the ange |02 will, under such conditions, have been moved into engagement with extension 90 of piston `18 and, therefore, -a drop in suction following the opening of the throttle will'not'be effective to move the piston to the left'. Moreover, the-further movement of the throttle toward open position does not cause any considerable movement of the piston to 'the right, because of 'the` nearly concentric shape |3012 of thelcam |30'. The above described` action is desirable because after la predetermined throttle opening isreached, temporary closing of? the choke valve -foiacceleration pure poses issubstantially unnecessary.

It will be understood thatl the rate of ymove-l ment ,of `thepiston 18 toward the right, and con--` sequently therate of movement of the choke toward open position will be determined by they movement of the dash pot piston 98 towardthe right, and it will also be apparent that the retardingveect of such dash pot piston will be progressively reduced as said piston moves to`' ward the right; Itis not necessary to retard the opening lmovement of lthechoke to yas .great `ay degree when said valve approaches its open posi-v tion as when said valve is more nearly closed. This' control ofy theretarding effect of the dash pot is brought about by the tapered slot previ" ously described, which is formed in the wallof the dash pot cylinder |00. v

It will also be apparent that the dash pot controls'the movement to the lefto'f piston '|8 when thethrottle isfclosed from an open position as the return spring can return the parts no more rapidly than the dash pot permits.

Coming now to the operation of the control switch by means of which the action of the starting motor is automatically regulated, it is obvious fromconsideration of the circuit diagram in Fig. '7, that the ignition switch and the switch comprising contacts |80 and |82 must be closed and whenever-the ignition switch'or the control switch isV open, the starting motor circuit is broken. When the engine is at rest, with the throttle closed, the ignition switch is open and also the control is open because the closing of the throttleV through the medium of the arm extending from cam |30 moves the rod operated thereby so far to the right'that it pushes the spring arm |84 so far to the right thatA the control switch is open.4 Under these conditions the suction operated latch is in the position shown in Fig. 5.

To start the engine, assuming the throttle is closed andthe ignition turned oi, it is necessary tov close the ignition `switch since this switch isfin series in theV starter control circuit and'also to move the throttle vsuilicientlytoward open position tok permit the rod 208 to move to the 'left enough to cause the control switch embodying contacts |80 and |82 to close. This movement of the throttle is approximately 35 or therefound desirable to provide the kdesired quantity ofrnixtur'e for starting purposes. The-'closing of theignition switch and the closing ofthe Cdn; trol switch as described, complete the control circuitwith the'result that the magneti-s operated to shift` the driving pinion into engagement with the flywheel gear and at the same time close theV main starting motor circuit, as previously described. The starter motor becomes operative then and will start the engine. As earlier pointed out, if the-enginejdoes notj start promptly land thecranking period is lprolonged without results,

, theoperator should open the'throttle for the purpose of relieving ooding, as previously described; When 'the engine starts torun under its own power, the actiongof Vthe engine suction is such asto move the high surfacev of the control `cani into engagement with the pin on spring arm |81' to open the control switch and break -the starter circuit when the starter willbeco'meinoperative.

`Aslong asvthe engine suction remainsrelatively high, the control cam will be heldin such pos'i7 Ytion that the vhigh surface is opposite the pin on the spring arm |84 which is adapted to en,- gage such'cam surface and will hold the -switch open.' If, however, the engine is operatingunder` prevent such action; it might be possibleto close abouts toward open` position, which has been' 75 heavy loadwith wide open throttle, the' suction`V 4would dropand if means'were'not provided/to the starting motor lcircuitand cause serio-us darn-' age to the starting system. This action is pre'-v vented by means of a latch member which is vcarried by the cam and which engages the pin` on the spring arm' |84 to prevent a'return of the controlcam to its.original-position` until the throttle has been allowed to close so aste-move the pin out of the path of the latch m'emberyfOf course, if the throttle isclosedjthe suction imrne-f` diately becomes high and the'cam will no'tbe) permitted to move to'a'position wherey thefcon trol switchcan be closed because'of the -h'igh sub?!` tion. If .the throttleV is again opened so t'lfiattlie" suction-drops, the latchwill becorrieagairrfe'e tive. 1 '-1 The spring detentl which controls the operation? of they cam and the latch member Ais an important' feature o'f this invention and makes it 'subst'a tially impossible' for the controlswitch to vb'e* closed under any operating conditions'wh'ich can` be met. It is obviously necessary that a device of this character must be constructedsothat the control switch cannot be opened during engine cranking orA else the starter 'circuiti wouldy '1 be broken and the engine would not beY started. Due tothe fact that the throttle is'generally in only a partly open position during cranking, thesuction may be higher whenthe engine isbeingv turned by the'startingf motor for the .purpose f starting it than when it is operating funder its j own power with a'.` relativelyvopenfthrottle and`I heavy load. It has been vfound necessary to pro'- vide a device which will' not vopen duringA crank# A ingunder a suctionof.` from 31/2 inches of mer-"i cury, but will hold openjduring operation'at a"v` fsuction much lower thanfthat. Thespring detent hereinbefore described,produces these results.

and because of the engagement of the',springy held ball with the calm memberL-thegcam cannot be movedby engine fsuction until a vacuumxof'f some 3.1/2 inches of` mercury isgfreached, butv after the bal-l ris disengaged from the recess invwhich 'f' it normally-seats inthe cam chamber, `the cam L will be held by a suction of las little: asa-half an inch .of mercury in. its positionwhereitwill hold vthe ,switch opexrj` .Thisieature of operation isof considerable importance because even when choke valve and for operating under apart throttle condition where the vacuum would normally be high enough to hold the control switch open, under such conditions the throttle might be in a position that therod 208 does not hold the switch open", the' it is to be understood that other forms mightbe adopted, all coming within the scope of the claims which follow.

` What is claimed is as follows:

1. A control mechanism for an internal com-r' bustion engine having a starting motor and a' carburetor for supplying mixture thereto which is provided with a choke valve for regulating the fuel air ratio of the mixture formed by said carburetor anda throttle for regulating the quantity of mixture supplied by such carburetor 'to the engine, means for automatically positioning the choke in accordance with temperature and engine suction, means for controlling the operation of the starting motor, and means operated by the throttle for modifying the action of the choke l valve and for operating said controlling means to cause the starting motor to become operative.

'2. A control mechanism for an internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which is Aprovided with a choke valve for regulating the fuel air ratio of the mixture formed by said carassaoes automatically positioning the choke in accordance with various operating conditions, a control switch for the starting motor, means operated by the throttle formodifying the action of the choke valve and for closing the control switch,

and means operable by engine suction for opening;

said control switch.

5. A control mechanism for an internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which is provided with a choke valve for regulating the fuel air ratio of the mixture formed by said carburetor and a throttle for regulating the quantity of mixture suppliedby such carburetor to the engine, a control unit including means for automatically positioning the choke in accordance with various operating conditions, a control switch forthe starting motor, means operated by the throttle for modifying the action of the choke valve and means operated by the throttle for holding the control switch open when the throttle is in closedl position.

6. A control mechanism for an.` internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which is provided with a choke valve for regulating the fuel air ratio of the mixture formed by said carburetor and a lthrottle for regulating the quantity of mixture supplied by such carburetor the latter makes buretor and a throttle for regulating the quan- Y tity of mixture supplied by said carburetor `to the engine, a. control unit including means for automatically positioning the choke in accordance with various operating conditions, a control switch for the starting motor, means operated by the throttle for modifying the action of the and means operable by the engine `for opening said control switch.

3. A control mechanism for an internal combustion engine having a starting motor and a y ance with various operating conditions, a control switch for the starting motor, means'operated by the throttle for modifying the action of the choke valve and for closing the control switch, and means operated by the engine for opening'said control switch whenl the engine becomes selfoperative and'for maintaining said control switch open as long as the engine continues to' run under its own power.

4. A control mechanism for an internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which is-provided with a choke valve for regulating the fuel air ratio of the mixture formed by i said carburetor and a throttle for. regulating the quantity of mixture supplied by said carburetor to the engine, a control unit including means for closing the control switch,y

tothe engine, a control unit including means for automatically positioning the choke in accordance with various operating conditions, a control switch for the starting motor, means operated by the throttle for modifying the action of the choke valve and means operated by the throttle for holding the control switch open,.said last named means being operable by the throttle when a predetermined movement toward open position to effect closing of theY control switch.

7. A control mechanism for an internal com- --Jbustion engine having a starting motor and a carburetor for supplying mixture thereto which is provided with an air choke valve for regulating the fuel air ratio of the mixture formed by said carburetor and a throttlefor regulating the quantity of mixture supplied lby such carburetor to the engine, means for automatically positioning the choke in accordance with engine suction and temperature, a control switch for the starting motor,throttle operated means for modifying the action of the choke and for closing said control switch to cause the starting motor to be energized and means operated by engine suction for opening said control switchY to cause the starting motor to become ineifective.

8. A control mechanism fora'n internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which is provided with a choke valve for regulating the fuel air ratio of the mixture-formed by said carburetor and a throttle for regulating the quanbecome effective, and means operable by engine suction to open said control switch.

9. A control mechanism for an internal combustion engine having a starting motor and a carburetor for supplying mixture thereto which valve for regulating the fuel air ratioof such charge,V means ior'c'ontrolling the position ofthe choke valve -in accordance with temperature and engine suction. a starting motor for'said engine, a control switch for controlling theactivlty'of the starting motor,` means operatedbyv the throttle for closing the controlA switch and means operated aseaoes by engine suction for modifying the'action of the y choke controllingmeans and for opening'the control switch when the engine starts to run. l w 20. In combination `with an internal combustion engine, a charge forming device thereforl having a throttle valve for fcontrolling thequantity of charge supplied to the engine and a choke valve for regulatingthe'fuel air ratio ofsuch charge, means'for controlling theposition ofthe choke valve in accordance with temperature andengine suction, a starting motor for said engine, a control switch for controllingA the activity of the starting motor, means #operated by the v throttle for closing the control switch and means operated by engine suction for modifying the-action of the choke controllingA means and for openingI the control switch when the engine starts to run, and

throttle ywhen moved toward open position to limit the movement of said suction operated memL ber sov that the mixture is not too greatlyenvfuel-and air in said mixture comprising thermally responsiverneansv and means operable by engine *Suction ior'variably regulating one ofv the componente of the fuel mixturaand-,a cam operable by the throttle for variably regulating the action o f the mixture controlling mechanismv in accord'- lance with different throttle positions,' saidy cam bein'g'so'formed that it is effective only during a part ofy the Vmovement; of the throttle toward its open position. t '.24. In combination with an internal combustion engine, a charge forming device for supplying combustible mixture thereto, said charge forming device having means for supplying fuel and air thereto toform aA combustible mixture i anda throttle for controlling the quantity of such mixture supplied to theengine, a choke valve for automatically controlling the proportions of fuel and air in said mixture comprising thermally responsive Vmeansoperable vto position the choke valve in accordance with temperature, a suction operated member operable when the suctionl ls high to reduce the proportions of fuel to air and when "the suction is low; to increase the proportion of fuelfto airfandvmeans operable by the riched, saidthr'ottlevoperated means being so constructed Athat it is effective only during a part of the movement of the throttle toward its open position.

switch for the starting `motor and an instrumentality operated by the throttlefor modifying the action of the'choke'valve and for closing the control switch, said instrumentality being so constructed that themodifying effect on the choke .Y

valve is brought about during the rst portion of the throttle movement toward open'position, but the closing vof the control switch is not ef fected until after a predetermined :opening of the throttle4 j Y 22.In combination with an internal combustion engine, a charge forming device for supplying combustible mixture thereto,V said charge' forming device having meansv forjsupplying fuel and air thereto to form a combustible mixture and a throttle for controlling thel quantityA of such mixture supplied tol the engine, mechanism -for automatically controlling the proportions of fuel and air in said mixture comprising thermally responsivemeans and means operable by engine choke valve, means valve when moved toA closed position to hold the 25. A control mechanism for an internal combustion 'engine Ihaving a starting motor and a carburetor for :supplying mixture thereto which is providedwith a choke valve for-'regulating' the fuel air ratio of the mixture formed by said carburetor ,andl av throttle for regulating the quantityof mixture supplied by such carburetor to theengine, av control unit including means for automatically positioning the choke in accordanceA Withvarious operating conditions, a control switchl forvthe startingmotor, means operated by thethrottle for modifying the action of the operated' by the throttle control switch openfin order to prevent operation of the Istarting motor when the engine is not running; said lastnamed means being operable by the throttle when it is moved a predetermined ing movements of the throttle when the engine is running. v

267A control mechanism for aninternal corn`- .bustion engine having a-startingmotor and a suction for variably regulating one of the components of the fuel mixture, and means operable by the throttle for variably regulating the action of the mixture controlling mechanismin accordf ance with different throttle positions,.said means being so constructed that'it produces an effect on the mixture controlling mechanism only 'during a part of the movement of the throttle toward open position. 23,y In combination with an internal cornbus tion engine, a charge forming device for supply# ing combustible mixture thereto. v'said charge lforming device having means for supplying' fuel and air thereto to form a combustible mixture l and a. throttle for controllingthe quantity of such mixture supplied toth'e engine, mechanismfor automatically controlling the proportions of carburetor for supplying mixture thereto which is provided with a choke vvalve for regulating the fuel vair ratio, of the mixture formed by said throttle whenl it is -moved amount toward open position to bring about the closing of saidcontrol switch, means operable by engine suction tonormally preventclosing of the ,control switch during operation of the engine under its own power, and additional means to\ Aprevent closing of the control switch when the engine is `so reduced upon an opening movement of the throttle as to bev ineffective Ato hold `said switch open. i

27. A control mechanism for an internal combustion engine having a starting motor and a vcarburetor' for supplying mixture thereto which is l0 provided with a choke valve for regulating the fuel air ratio of the mixture formed by said 4carburetor and a throttle "for regulating the -quantity of mixture supplied by such carburetor to the engine, a control unit including means for l5 automatically positioning the choke in accordance with various operating conditions, a control switch for the starting motor, means loperatedby the throttle for modifying the action of the choke valve, means operated by the throttle valve when gg moved to closed position to hold the control switch open in order to prevent operation of the starting motor when the engine is not running. said last named means being operablev by'the throttle when it is moved a predetermined amount toward (men u position to bring about the closing of said control switch. means operable by Aengine suction to normally prevent closing of the control switch during operation of the engine under its own power, and a latch mechanism for preventing the 3 closing lof the control switch if the suction operated means becomes ineffective.

l28. A control mechanism for an internal combustion enginehaving a starting motor and a carburetor for supplying mixture thereto which u is provided with a choke valve for regulating theV fuel air ratio of the mixture `formed by said carburetor and a throttle for regulating the quani tity of mixture supplied by such carburetor to the engine,a control unit including meansfor auto- 4o matically positioning the choke in accordancev with various operating conditions, acontrol switch for the starting motor, means operated by the throttle for modifying the action lof the choke valve, means operated by th'e throttle valvev when 45 moved to closed position to hold the control switch open inv order toprevent operation of the str rting motor when ,the engine is not running, said last named means being operableby the throttle when it is moved a predetermined amount toward open/ 50 position to bring about the closing of said control switch, means operable by engine suction tov normally prevent/closing of the control switch during operation of the engine under its own power, a

latch mechanism for preventing the closing of the' i5:

control switch when th'e'enginesuction becomes ir effective to hold said switch lopen and means for releasing said latch mechanismV when the engine becomes inoperative,v so that opening of the throttle is effective to close said switch and cause 50 the starting motor to become effective.

l29. lA control mechanism for an internal combustion 'engine having a starting-motor and a carburetor for supplying mixture thereto which is provided with a choke valve for regulating the 05 fuel'v air ratio of the mixture formed by' said carburetor and a throttle for regulating the quantity of mixture supplied by such carburetor to the engine, a control unit including 'means for y. open in order to-prevent operation of the starting voperable by engine suction to normally prevent automatically positioning the chokein accordance 10 with various yoperating conditions, la control' l switch forthe starting motor, means 'operated by the 'throttle for modifying the action of the chokey valve, means operated' by the throttle valve when moved to closed position to hold the control switch 1| motor when the. engine isnot running, said last ynamed 'means being operable by .the throttle when it i's-moved a predetermined amount toward open llziosition to bring about the closingof said control switch, means operable by engine `suction to normally `prevent closing of-the control switch duringr operation of the engine under its own l is provided .withachoke valve for regulating the fuel air ratio. of ther mixturer formed by said carburetoranda throttle for regulatingthe quan'- tity of mixture. supplied-by such carburetor to the engine,fa,control-.unit including means for automatically positioning the vchoke in Yaccordance with. various operating conditions`,"`a con-` trol switch for thestartingmotor,.means operated `bythe throttle for modifying theaction of the -chokc"va1ve, means operated by the throttle valvefwhen moved to closed .position Vtoholdthe control switchopen inorder to prevent opera. tionof the starting motor .when the engine is" not running, said last named means being oper;Y able by the throttle when it is moved 'a pre- I determined 'amount toward'open. position to bring about the closing of saidcontrol switch, means closing of thecontrol switch during operation ofthe 'engine under-A its own power, a latch mech;

anism for. preventing the closing of the controly switch when the engine suction becomes ineffective to hold said switch open, and. means 'oper- Y able by the-throttle as said throttlefii's moved. toward closedfposition to release the said latch mechanism, y Y

`31. A control mechanismfforfanintern'al combustion engine., havingfa starting 'motori and a f carburetor for-supplyingvmixtnre thereto whichl is providedv with' a cholcevalve` for regulating" the. fuel air/:'ratioofthe-'mixture formed by'said` carburetor and a--throttle for regulating the quantity of mixture supplied vby such-carburetor to the engine, 'a control unit includingI means for automatically Apositioning 'the chcke in' Vaccordance with-L'various operating conditions, a control switch f or the starting motor, means operated by the throttle for .modifying the action of the choke valve, means operatediby the'th'rottle forlet'fecting the closing oflthe control switch to cause the starting motor to -become operative and vstart the engine, a member movable by en-l gine suction whenthe ,engine becomes 'self-operative to a position where it is* effective'to hold' the control switch open, and adaptedtobe maintainedjin such position. as lcng as thev enginey is above a predetermined amount, and means -toprevent movement of said suction operatedy member toits ineffective position' when saidr suction -.falls belo'w said predeterminedl annimmt.'v

,32.IA control mechanismffor an internal combustion engine having. a lstarting motor and a carburetor yfo/r supplying mixture thereto which i is provided with a chokevalve for regulating the fuel air ratio of the mixture' formed by. said carburetor and a throttlefor regulating the quantity of mixturegsupplied by such carburetor`- to the engine, a control unit including -means for automatically positioning the choke in acby the .throttle for choke vaivejmeans cordancey.,w-ith .various operating conditions, a.

controll switch yfor,y thestartingmotor, ,means operated by the-throttle.formodifying the action ,of the choke valveme'ansoperated.by the throttle for .effecting the closingl-of the control l switch and 'start ,thejengine' a member movable by engine suctionwhen I.the engine Vbecmiesl `selfoperative .tofaposition*whereit is `effective to hold thecontrol switch open,and adapted to be g maintained in such positionv as long as .the en abovea predetermined amount, f

the engine, a' .controlunltlncluding means for automaticallypositioning the choke in accord. ancefwith various operating conditions, a control switch tor ,the starting `motor,.`m eans yoperated modifying the Aaction* oflthe eil'ecting the' closing of the control switch to cause the startingfmotor to `become operative and start the engine, amemher movable by engine suctiorivvhe'n the Aengine vbecomes selfoperative to a position :where'it is eiective to hold the control'switch open; andadaptedto be maintained fin such positioneslonguasthe engine is above .a predeterminedv amount, and' a latch jelement secured `tonne ofjthe contact elements of the control switch and .adapted `to engage said'member and neig ,it `lmits ,directive pgsiuon when the rSiw'iion falle elew .Said ,predetermined amount.

34. A'control mechanism forvanrinternal com- ,bustionengie hanvixiga starting, motor and a carburetor Ifor supplying mixture thereto which is provided vvvith ariclioke valve for regulating,the

fuel lair ratio )of themigtture. formed by said carburetor andajthrottle iorijegulgltig the ,quantity of n iixtufre 'supplied by' such carburetor tothe engine, fa control unit'lncludin'g means forautomatically positioningithe choke in accordance op retedpy the throttle forl the vthrottleV for ,to causethe starting,t motor ,to become operative with various"operating conditions, a controll switchffor the 4starting motor; means operated by the throttle for modifying the action of the choke valve,r means operated` bythe lthrottle for effecting" the closing of the control switch to cause the starting motor to become operative and start the engine; amembe'r movable byvfengine suction when'. the engine becomes` selig-operative to a posltion where it isl efectivefto. control switch open, andadaptedft'o tained inwsuchpo'sition'yas long as the above a predetermined amount, -a,1a tch to engage said member tohold it 'inits effective position when the suction falls below said predetermined amount and means operated bythe throttle for releasing said latch.

35. A control mechanism for an internal comliold the 'bustion engine having a starting motor and a carburetor for supplyingiznixtu're thereto which is provided with la choke valve for regulating the fuel air ratio of the mixture formedv by said carburetor and a throttle for regulating the quanbe mainenginev ids' tity of mixture supplied by such rcarburetor to.

the engine, a control unit including means for automatically positioning the choke in accord- .ance with various operatingconditions, a control switch for the starting motorymeans operated b y modifying `the action of the choke valve, eans operated by the throttle for effecting the' closing of the control switch'to cause the starting motor to become operativeand start the engine,1 a member movableby engine the engine becomes self-operative to a positionwhereit is effective to hold the conopen, and adapted tobe lmaintained .it is moved.

36. A control mechanism for an internal com bustion engine having a starting. motor and a carburetor forfsupplying mixture4 thereto which starting motor.

37. A control mechanism for an internal combustion engine having a mixture regulating means and closing the starter control switch to effect energization of the starting motor.

38. In a starting apparatus for internal combustion I v engines having a current source, a start- H. JORGENSEN. C. DERMOND.

' CLARENCE LAWRENCE 

